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Relationship between vegetation structure and microenvironment in Fagus grandifolia *** forest relicts in Mexico

Journal of plant Ecology 2018年第2期11卷 237-247页

作者： Ernesto ChRodríguez-Ramírez Arturo Sánchez-González gregorioángeles-pérez Laboratorio de Biogeografía y Sistemática Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMéxico Laboratorio de Ecología de poblaciones Centro de Investigaciones BiológicasUniversidad Autónoma del Estado de HidalgoCiudad UniversitariaCarretera Pachuca-Tulancingo Km.4.5Mineral de la Reforma 42184Hidalgo postgrado en Ciencias Forestales Colegio de PostgraduadosMontecillo 56230TexcocoEstado de MéxicoMéxico

Aims Changes in the structure and composition of forests,whether caused by natural or anthropic events,alter the microenviron-ment,sometimes *** the local environment has a direct impact on basic ecological processes,this has become a key component of *** beech forests(Fagus grandi-folia ***)in the Sierra Madre Oriental are restricted to sites with specific climate,soils and topography,making them an ideal natural system for ecological *** objectives of this study were to identify the relationship between the microen-vironment and the tree and shrub structure and composition of Mexican beech forests in the state of Hidalgo,and to compare the floristic similarity of these forests on the country scale using data from seven *** Specimens were collected for a period of one year at all locali-ties in the state of Hidalgo where beech forests are *** each locality,five 400 m2 plots were established,and structural attributes(basal area,coverage,density and species richness)and six environmental variables were measured in the *** relationship between structure and microenvironment was estimated by simple correlation and canonic correspondence analysis(CCA).in addition,floristic similarity between different beech forest localities in the Sierra Madre Oriental was esti-mated by correspondence analysis(CA).Important Findings Twenty tree species and eight shrub species were identified;at all localities studied *** *** dominated the *** multivariate analysis indicated that(i)in the four localities in the state of Hidalgo,all microenvironmental variables except pH are related to the variation observed in species composition and structure;(ii)the El Gosco locality had both tree and shrub species and microenvironmental factors different from those observed in the Fagus forests at the other localities in the study and(iii)the localities studied in order to draw country-scale compa

关键词： Canonical correspondence analysis fagus forest floristic composition Mexico montane cloud forest richness

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Land cover change and carbon stores in a tropical montane cloud forest in the Sierra Madre Oriental,Mexico

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Journal of Mountain Science 2018年第10期15卷 2136-2147页

作者： Edgar G.LEIJA-LOREDO Numa p.pAVóN Arturo SáNCHEZ-GONZáLEZ Rodrigo RODRIGUEZ-LAGUNA gregorioángeles-pérez Center for Biological Research Autonomous University of Hidalgo.42184 HidalgoMexico Institute oJ:Ag ricultural Sciences Academic Area of Forestry EngineeringAutonomous University of Hidalgo.43600 HidalgoMexico postgraduate School Campus MontecilloPostgraduate in Forest Sciences.56230 Estado de MexicoMexico

Tropical montane cloud forest is one of the ecosystems with the highest biomass worldwide, representing an important carbon store. Globally its deforestation index is –1.1%, but in Mexico it is higher than –3%. Carbon estimates are scarce globally, particularly in Mexico. The objective of this study was to simulate future land-cover scenarios for the Sierra Madre Oriental in Mexico, by analyzing past forest cover changes. Another objective was to estimate stored carbon in the two study areas. These objectives involve the generation of information that could be useful inputs to anti-deforestation public policy such as the REDD+ strategy. Remote sensing was used to measure land cover change and estimate carbon stocks. Satellite images from 2015, 2000 and 1986 were used, and Dinamica EGO freeware generatedmodels of future projections. Between 1986 and 2015, 5171 ha of forest were converted to pasture. The annual deforestation rates were –1.5% for Tlanchinol and –1.3% for the San Bartolo Tutotepec sites. Distance to roads and marginalization were highly correlated with deforestation. By 2030, an estimated 3608 ha of forest in these sites will have been converted to pasture. Stored carbon was estimated at 16.35 Mg C ha-1 for the Tlanchinol site and 12.7 Mg C ha-1 for the San Bartolo site. In the Sierra Madre Oriental deforestation due to land cover change(–1.4%) is higher than levels reported worldwide. Besides having high values of stored carbon(14.5 Mg C ha-1), these forests have high biodiversity. The models' outputs show that the deforestation process will continue if action is not taken to avoid the expansion of livestock pasturing. This can be done by paying incentives for forest conservation to the owners of the land. The results suggest that REDD+ is currently the most viable strategy for reducing deforestation rates in tropical montane cloud forests in Sierra Madre Oriental.

关键词： Cloud forest Carbon stores C mitigation Climate change Dinamica EGO Forest management Remote sensing.

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presynaptic endoplasmic reticulum architecture and hereditary spastic paraplegia

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Neural Regeneration Research 2024年第3期19卷 485-486页

作者： Juan Josépérez-Moreno Instituto de Biomedicina de Sevilla(IBiS) Hospital Universitario Virgen Del Rocío/CSIC/Universidad de Sevillaand Departamento de Biología CelularFacultad de BiologíaUniversidad de SevillaSevilleSpain

Hereditary spastic paraplegia(HSp)is a clinically and genetically heterogeneous neurodegenerative disorder,characterized primarily by progressive spasticity and weakness in the lower *** ients can also experience peripheral neuropathy,cognitive impairment,and other neurological *** date,more than 80 genes have been implicated in HSp,encompassing various cellular components,although mutations in genes encoding endoplasmic reticulum(ER)-shaping proteins are the most prevalent(parodi et al.,2017).ER-shaping proteins are generally known for regulating the tubulation and curvation of the ER,but most of them show additional functions,including fusion of ER tubules,microtubule-severing,ER autophagy,lipid droplet synthesis,contact sites with other organelles(Öztürk et al.,2020).This highlights the complexity of studying the role of these proteins and the link between ER function and HSp.

关键词： reticulum endoplasmic

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Non-participation of asymptomatic candidates in screening protocols reduces early diagnosis and worsens prognosis of colorectal cancer

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World Journal of Gastroenterology 2024年第26期30卷 3198-3200页

作者： Sergio pérez-Holanda Office of Regional Viceministry of Health Regional Viceministry of HealthOviedo 33005AsturiasSpain

The Agatsuma et al’s study shows that despite the evidence of the benefits of an early colorectal cancer(CRC)diagnosis,through screening in asymptomatic subjects,up to 50%of candidates reject this option and many of those affected are diagnosed later,in advanced *** efficacy of screening programs has been well-established for several years,which reduces the risk of CRC morbidity and mortality,without taking into account the test used for screening,or other ***,a significant proportion of patients remain unscreened,so understanding the factors involved,as well as the barriers of the population to adherence is the first step to possibly modify the participation *** barriers could include a full range of social and political aspects,especially the type of financial provision of each health *** Japan,health services are universal,and this advantageous situation makes it easier for citizens to access to these services,contributing to the detection of various diseases,including ***,the symptomatic CRC group had a lower early-stage diagnosis rate than the patients detected during follow-up for other comorbidities,and symptomatic and cancer screening groups showed similar early-stage diagnosis.

关键词： Colorectal neoplasms Cancer registry Diagnostic route Cancer screening Stage at diagnosis

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Some facets of the Mg/Na_(3)VCr_(0.5)Fe_(0.5)(pO_(4))_(3) battery

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Chinese Chemical Letters 2024年第10期35卷 469-473页

作者： gregorio F.Ortiz Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing Institute of Luminescent Materials and Information DisplaysCollege of Materials Science and EngineeringHuaqiao UniversityXiamen 361021China

Magnesium rechargeable batteries(MRBs)present opportunities for grid-scale energy storage applications as a complement to Li-ion batteries(LIBS).The major challenges are the low reversible capacity,inferior cycling stability and unsatisfactory energy ***_(3)VCr_(0.5)Fe_(0.5)(pO_(4))_(3) with a well-defined NASIONtype structure is used as cathode in Mg ***-electrons reaction(~116 m Ah/g),1.5 V average voltage and 65%of capacity retention over 100 cycles are *** is inserted by a biphasic reaction with the participation of V3+/V4+/V5+redox couples in the electrochemical reaction while the non-active redox couples such as Cr^(3+)/Cr^(4+)and Fe2+/Fe^(3+)served as stabilizer to buffer the volume variation.A thermal stability up to~412℃ is also ***,incorporating a mixture of three transition metal(V/Cr/Fe)in this type of structures will broaden new perspectives for realizing high performance cathodes for MRBs.

关键词： Multi-electron reaction Mg batteries NASICON Na_(3)VCr_(0.5)Fe_(0.5)(pO_(4))_(3) Ironand chromium doping

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Calibration of the DEM sliding friction and rolling friction parameters of a cohesionless bulk material

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particuology 2024年第9期92卷 126-139页

作者： Jonatan Marín pérez Tugrul Comlekci Yevgen Gorash Donald MacKenzie University of Strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete element method(DEM)has become a valuable tool for understanding the mechanical behaviour of granular assemblies,however,the accuracy of the DEM simulations depends on several interaction parameters such as the sliding friction and rolling friction ***,these parameters are estimated using bulk calibration approach(BCA)where the draw down test has been suggested as an effective way to approach these *** test provides up to four bulk criteria,the angle of repose,shear angle,mass flow rate and the mass loss which are used to narrow down the possible ***,there is still more research needed around it to fully understand how this methodology *** experimental and numerical study was carried out using the draw down test to assess the influence of different mass flow rates and particle shapes on DEM parameters for a cohesionless bulk *** is concluded that use of multi-sphere particles and three aperture sizes in the draw down test to calibrate the sliding and rolling friction parameters of a cohesionless bulk material can converge to a small feasible region in which a single combination of the friction coefficients can be *** calibrated sliding and rolling friction coefficients were validated using multi-sphere particles,where the maximum deviation was 5.9%from the experimental values.

关键词： Discrete element method Calibration Draw down Sliding friction Rolling friction particle shape

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Assessment of energy consumption,environmental effects and fuel costs of the bus rapid transit system in Bogotá(Colombia)

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Clean Energy 2024年第3期8卷 34-47页

作者： Jhon Jairo pérez Luis Hernando Correa poul AlbergØstergaard pedro Cabrera Universidad de La Salle-Engineering Faculty Electrical DepartmentCampus La CandelariaBogota D.C.Colombia Aalborg University Department of PlanningRendsburggade 149000 AalborgDenmark University of Las palmas de Gran Canaria Department of Mechanical EngineeringCampus Universitario de TafiraLas Palmas de Gran CanariaSpain

Colombia aims to boost the utilization of mass transportation systems in its major cities while simultaneously reducing greenhouse gas emissions by 20%,in alignment with the commitments of the COp21 *** 2020,the transport sector in Colombia accounted for 34.4%of the country’s energy demand and was responsible for~49%of its total CO_(2) *** article presents an assessment of energy consumption,environmental effects and the fuel costs of Bogotá’s bus rapid transit system based on the Activity,Share,Intensity,Fuel methodology.A long-term analysis spanning from 2021 to 2040 was developed using the long-range energy alternatives planning *** conduct this assessment,the tool was calibrated using data from 2019 and *** distinct scenarios based on energy policies implemented in Bogotáwere examined:Business as Usual,Fast Transition,High Growth and Low *** energy consumption and environmental effects,the results underscore the pivotal role of diversifying energy sources and reducing reliance on fossil fuels such as ***,the analysis emphasizes the urgent need to accelerate the transition to alternative energy sources such as natural gas and electricity.

关键词： ASIF energy consumption environmental effects LEAp long-term energy model public transport

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primary repair of esophageal atresia Gross type C via thoracoscopic magnetic compression anastomosis:Is it the best option?

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1474-1481页

作者： Sonia pérez-Bertólez Jorge Godoy-Lenz Department of pediatric Surgery Sant Joan de Deu HospitalUniversity of BarcelonaBarcelona 08950Spain Department of pediatric Surgery Clínica Alemana of SantiagoSantiago 7650568Chile

Magnetic compression anastomosis is a promising treatment option for patients with complex esophageal atresia;but,at the present time,should not be the first therapeutic option in those cases where the surgeon can per... 详细信息

关键词： Esophageal atresia Tracheoesophageal fistula Thoracoscopy Magnamosis Magnetic anastomosis

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Nonlinear dynamics of the reversed shear Alfvén eigenmode in burning plasmas

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plasma Science and Technology 2024年第5期26卷 1-16页

作者：王涛魏士朝 Sergio BRIGUGLIO gregorio VLAD Fulvio ZONCA 仇志勇 Institute for Fusion Theory and Simulation and School of physics Zhejiang UniversityHangzhou 310027People’s Republic of China Center for Nonlinear plasma Science ENEA C.R.FrascatiFrascati 00044Italy Fusion and Nuclear Safety Department ENEA C.R.FrascatiFrascati 00044Italy

In a tokamak fusion reactor operated at steady state,the equilibrium magnetic field is likely to have reversed shear in the core region,as the noninductive bootstrap current profile generally peaks *** reversed shear Alfvén eigenmode(RSAE)as a unique branch of the shear Alfvén wave in this equilibrium,can exist with a broad spectrum in wavenumber and frequency,and be resonantly driven unstable by energetic particles(Ep).After briefly discussing the RSAE linear properties in burning plasma condition,we review several key topics of the nonlinear dynamics for the RSAE through both wave-Ep resonance and wave-wave coupling channels,and illustrate their potentially important role in reactor-scale fusion *** means of simplified hybrid MHD-kinetic simulations,the RSAEs are shown to have typically broad phase space resonance structure with both circulating and trapped Ep,as results of weak/vanishing magnetic shear and relatively low *** the route of wave-Ep nonlinearity,the dominant saturation mechanism is mainly due to the transported resonant Ep radially decoupling with the localized RSAE mode structure,and the resultant Ep transport generally has a convective *** saturated RSAEs also undergo various nonlinear couplings with other collective *** typical routes as parametric decay and modulational instability are studied using nonlinear gyrokinetic theory,and applied to the scenario of spontaneous excitation by a finite amplitude pump *** RSAEs could naturally couple and induce the spectral energy cascade into a low frequency Alfvénic mode,which may effectively transfer the Ep energy to fuel ions via collisionless Landau ***,zero frequency zonal field structure could be spontaneously excited by modulation of the pump RSAE envelope,and may also lead to saturation of the pump RSAE by both scattering into stable domain and local distortion of the continuum structure.

关键词： reversed shear Alfvén eigenmode energetic particle nonlinear gyrokinetic theory saturation burning plasma

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protein glycation:a wolf in sweet sheep’s clothing behind neurodegeneration

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Neural Regeneration Research 2024年第5期19卷 975-976页

作者： Ana B.Uceda Francisco Leal-pérez Miquel Adrover Institut Universitari d’Investigacióen Ciències de la Salut(IUNICS) Institut d’InvestigacióSanitària Illes Balears(IdISBa) Departament de Química Universitat de les Illes BalearsCtraPalma de MallorcaSpain

At the beginning of the 16th century,paracelsus coined the maxim:“the dose makes the poison”.This principle can be applied to all living organisms,including organs and *** brain and its glial and neuronal cells are ... 详细信息

关键词： organs sheep sweet

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